'Right.' Rebus checked that the small cassette recorder still had some tape left to run. 'Give me a physical description of this Neil character, will you?'

'Tall, skinny, short brown hair. Kind of spotty face, but always clean. Usually wore jeans and a denim jacket. Carried a big black holdall with him.'

'Any idea what was in it?'

'I got the feeling it was just clothes.'

'Okay.'

'Anything else?'

'Let's talk about the pentagram. Someone has been back to the house and added to it since these photographs were taken.'

Charlie said nothing, but did not look surprised.

'It was you, wasn't it?'

Charlie nodded.

'How did you get in?'

'Through the downstairs window. Those wooden slats couldn't keep out an elephant. It's like an extra door. Lots of people used to come into the house that way.'

'Why did you go back?'

'It wasn't finished, was it? I wanted to add the symbols.'

'And the message.'

Charlie smiled to himself. 'Yes, the message.'

'"Hello Ronnie",' Rebus quoted. 'What's that all about?'

'Just what it says. His spirit's still in the house, his soul's still.there. I was just saying hello. I had some paint left. Besides, I thought it might give somebody a fright.'

Rebus remembered his own shock at seeing the scrawl. He felt his cheeks redden slightly, but covered the fact with a question.

'Do you remember the candles?'

Charlie nodded, but was becoming restless. Helping police with their inquiries was not as much fun as he had hoped.

'What about your project?' said Rebus, changing tack.

'What about it?'

'It's on demonism, isn't it?'

'Maybe. I haven't decided yet.'

'What aspect of demonism?'

'I don't know. Maybe the popular mythology. How old fears become new fears, that sort of thing.'

'Do you know any of the covens in Edinburgh?'

'I know people who claim to be in some of them.'

'But you've never been along to one?'

'No, worse luck.' Charlie seemed suddenly to come to life. 'Look, what is all this? Ronnie OD'd. He's history. Why all the questions?'

'What can you tell me about the candles?'

Charlie exploded. 'What about the candles?'

Rebus was all calmness. He exhaled smoke before responding. 'There were candles in the living room.' He was getting close to telling Charlie something Charlie didn't seem to know. All during the interview, he had been spiralling inwards towards this moment.

'That's right. Big candles. Ronnie got them from some shop that specialises in candles. He liked candles. They gave the place ambience.'

'Tracy found Ronnie in his bedroom. She thinks he was already dead.' Rebus's voice became lower still, and as flat as the desktop. 'But by the time she'd phoned us, and an officer had turned up at the house, Ronnie's body had been moved downstairs. It was laid out between two candles, which had been burnt down to nothing.'

'There wasn't much left of those candles anyway, not when I left.'

'You left when?'

'Just before midnight. There was supposed to be a party somewhere on the estate. I thought I might get invited in.'

'How long would the candles have burned for?'

'An hour, two hours. God knows.'

'How much smack did Ronnie have?'

'Christ, I don't know.'

'Well, how much would he normally use at any one time?'

'I really don't know. I'm not a user, you know. I hate all that stuff. I've got two friends who were in my sixth form. They're both in private clinics.'

'That's nice for them.'

'Like I said, Ronnie hadn't been able to find any stuff for days. He was a bit whacked out, just about to fall right over the edge. Then he came back with some. End of story.'

'Isn't there much about then?'

'So far as I know, there's plenty, but don't bother asking for names.'

'So if there's plenty, how come Ronnie was finding it so hard?'

'God knows. He didn't know himself. It was like he'd suddenly become bad news. Then he was good news again, and he got that packet.'

It was time. Rebus picked an invisible thread from his shirt.

'He was murdered,' he said. 'Or as good as.'

Charlie's mouth opened. The blood drained from his face, as though a tap had been opened somewhere. 'What?'

'He was murdered. His body was full of rat poison. Self-inflicted, but supplied by someone who probably knew it was lethal. A lot of work was then done to manoeuvre his body into some kind of ritualistic position in the living room. Where your pentagram is.'

'Now wait -'

'How many covens are there in Edinburgh, Charlie?'

'What? Six, seven, I don't know. Look -'

'Do you know them? Any of them? I mean know them personally?'

'Christ, man, you're not going to pin this on me!'

'Why not?' Rebus stubbed out his cigarette.

'Because it's crazy.'

'Seems to me it all fits, Charlie.' String him out, Rebus was thinking. He's already stretched to snapping point. 'Unless you can convince me otherwise.'

Charlie walked to the door purposefully, then paused.

'Go on,' Rebus called, 'it's not locked. Walk out of here if you like. Then I'll know you had something to do with it.'

Charlie turned. His eyes seemed moist in the hazy light. A sunbeam from the barred window, penetrating the frosted glass, caught motes of dust and turned them into slow-motion dancers. Charlie moved through them as he returned to the desk.

'I didn't have anything to do with it, honest.'

'Sit down,' said Rebus, a kindly uncle now. 'Let's talk some more.'

But Charlie didn't like uncles. Never had. He placed his hands on the desk and leaned down, looming over Rebus. Something had hardened somewhere within him. His teeth when he spoke glistened with venom.

'Go to hell, Rebus. I see what you're up to, and I'm damned if I'm going to play along. Arrest me if you like, but don't insult me with cheap tricks. I did those in my first term.'

Then he walked, and this time opened the door, and left it open behind him. Rebus got up from the desk, switched off the recorder, took out the tape and, pushing it into his pocket, followed. By the time he reached the entrance hall, Charlie had gone. He approached the desk. The duty sergeant looked up from his paperwork.

'You just missed him,' he said.

Rebus nodded. 'It doesn't matter.'

'He didn't look too happy.'

'Would I be doing my job if they all left here laughing and holding their sides?'

The sergeant smiled. 'I suppose not. So what can I do for you?'

'The Pilmuir overdose. I've got a name for the corpse. Ronnie McGrath. Originally from Stirling. Let's see if we can find his parents, eh?'

The sergeant scribbled the name onto a pad. 'I'm sure they'll be delighted to hear how their son is doing in the big city.'

'Yes,' said Rebus, staring towards the front door of the police station. 'I'm sure they will.'

John Rebus's flat was his castle. Once through the door, he would pull up the drawbridge and let his mind go blank, emptying himself of the world for as long as he could. He would pour himself a drink, put some tenor sax music on the cassette machine, and pick up a book. Many weeks ago, in a crazed state of righteousness, he had put up shelves along one wall of the living room, intending his sprawling collection of books to rest there. But somehow they managed to crawl across the floor, getting under his feet, so that he used them like stepping-stones into the hallway and the bedroom.

He walked across them now, on his way to the bay window where he pulled down the dusty Venetian blinds. The slats he left open, so that strawberry slants of evening light came pouring through, reminding him of the interview room....

No, no, no, that wouldn't do. He was being sucked back into work again. He had to clear his mind, find some book which would pull him into its little universe, far away from the sights and smells of Edinburgh. He stepped firmly on the likes of Chekhov, Heller, Rimbaud and Kerouac as he made his way to the kitchen, seeking out a bottle of wine.

There were two cardboard boxes beneath the kitchen worktop, taking up the space where the washing machine had once been. Rhona had taken the washing machine, which was fair enough. He called the resultant space his wine cellar, and now and then would order a mixed case from a good little shop around the corner from his flat. He put a hand into one of the boxes and brought out something called Chateau Potensac. Yes, he'd had a bottle of this before. It would do.

He poured a third of the bottle into a large glass and returned to the living room, plucking one of the books from the floor as he went. He was seated in his armchair before he looked at its cover: The Naked Lunch. No, bad choice. He threw the book down again and groped for another. Dr Jekyll and Mr Hyde. Fair enough, he'd been meaning to reread it for ages, and it was blissfully short.

He took a mouthful of wine, sloshed it around before swallowing, and opened the book.

With the timing of a stage-play, there was a rapping at the front door. The noise Rebus made was somewhere between a sigh and a roar. He balanced the book, its covers open, on the arm of the chair, and rose to his feet. Probably it was Mrs Cochrane from downstairs, telling him that it was his turn to wash the communal stairwell. She would have the large, imperative card with her: IT IS YOUR TURN TO WASH THE STAIRS. Why she couldn't just hang it on his door like everyone else seemed to do ...?

He tried to arrange a neighbourly smile on his face as he opened the door, but the actor in him had left for the evening. So there was something not unlike pain rippling his lips as he stared at the visitor on his doormat.

It was Tracy.

Her face was red, and there were tears in her eyes, but the redness was not from crying. She looked exhausted, her hair cloying with sweat.

'Can I come in?' There was an all too visible effort in her voice. Rebus hadn't the heart to say no. He pushed the door open wide and she stumbled in past him, walking straight through to the living room as though she'd been here a hundred times. Rebus checked that the stairwell was empty of inquisitive neighbours, then closed the door. He was tingling, not a pleasant feeling: he didn't like people visiting him here.

Especially, he didn't like work following him home.

By the time he reached the living room, Tracy had drained the wine and was exhaling with relief, her thirst quenched. Rebus felt the discomfort in him increase until it was almost unbearable.

'How the hell did you find this place?' he asked, standing in the doorway as though waiting for her to leave.

'Not easy,' she said, her voice a little more calm. 'You told me you lived in Marchmont, so I just wandered around looking for your car. Then I found your name on the bell downstairs.'

He had to admit it, she'd have made a good detective. Footwork was what it was all about.

'Somebody's been following me,' she said now. 'I got scared.'

'Following you?' He stepped into the room now, curious, his sense of encroachment easing.

'Yes, two men. I think there were two. They've been following me all afternoon. I was up Princes Street, just walking, and they were always there, a little way behind me. They must've known I could see them.'

'What happened?'

'I lost them. Went into Marks and Spencer, ran like hell for the Rose Street exit, then dived into the ladies' in a pub. Stayed in there for an hour. That seemed to do the trick. Then I headed here.'